The research, published in the international edition of “Angewandte Chemie”, exemplifies the power of combining theoretical and experimental approaches in nanoscale characterization.
The adsorption geometry of functional molecules plays a pivotal role in determining their behavior at interfaces, which is crucial for applications in catalysis, photovoltaics, and molecular electronics. However, the lack of suitable in situ methods has made it challenging to understand and control the orientation of adsorbates, hindering the rational design of devices.
The research team, including RESOLV members Prof. Katrin F. Domke and Prof. Marialore Sulpizi in cooperation with Max Planck Institute for Polymer Research, employed a comprehensive approach that integrated tip-enhanced Raman spectroscopy (TERS), density functional theory (DFT), and molecular dynamics (MD) simulations. This combined methodology enabled them to address the long-standing controversy surrounding the adsorption geometry of trimesic acid on copper surfaces.
Their findings revealed that subtle energy differences in adsorbate-substrate-solvent interactions, on the scale of 0.25 eV, are critical in determining the molecular orientation at solid/liquid versus solid/gas interfaces. This discovery underscores the importance of quantitative in situ nanoscale characterization for the rational design of functional molecular interfaces.
The study highlights the strength of integrating theoretical and experimental techniques. Using TERS provided in situ, nanoscale chemical information, while DFT and MD simulations offered complementary insights into the energetic and dynamic aspects of the adsorption process.
This cooperative approach not only resolved a prevailing controversy but also set a precedent for future research in the field. As we continue to explore the nanoscale world, such interdisciplinary collaborations will be key to unlocking new possibilities and advancements.